Written following the Italian war for independence by a sub-lieutenant who had fought in the siege of Rome in 1870, Heart is the fictional diary of a boy's third year in a Turin municipal school. It was written to foster juvenile appreciation of the newfound Italian national unity, which the author had fought for in the recent war.

The book is often highly emotional, even sentimental, but gives a vivid picture of urban Italian life at that time. A master, introducing a new pupil, tells the class, "Remember well what I am going to say. That this fact might come to pass--that a Calabrian boy might find himself at home in Turin, and that a boy of Turin might be in his own home in Calabria, our country has struggled for fifty years, and thirty thousand Italians have died."

The novel became internationally popular, and has been translated into over twenty-five languages, and is part of the UNESCO Collection of Representative Works.

Edmondo de Amicis (1846-1908) established a reputation as a writer in various genres after his experience as a soldier.